Subfamily Harpagonchinae

Diagnosis (modified from Decraemer & Smol 2006 and Tchesunov, 2014): Cuticle with homogenous ornamentation without lateral differentiation. Anterior sensilla in three separate circles with the four cephalic sensilla setiform. Buccal cavity with three movable triangular-shaped mandibles with anterior solid hooks. Pharynx enlarged anteriorly around the mandibular apparatus and posteriorly widened with or without terminal bulb. Males with precloacal supplements present (cup-shaped) or absent. The genera of this sub-family are either considered ectoparasites (Decraemer & Smol 2006) or ectosymbionts (Tchesunov 2014) of polychaetes in marine environments.